Personal digital assistants (PDA) and other hand-held or pocketable computers have become an increasingly important tool for many users that require mobile data management. Improved computing power enabled PDAs to run complex tasks (e.g., database applications), while at the same time the development of smaller and more efficient storage enabled relatively large quantities of data (i.e., in excess of 10 MB) to be stored. With increased computing and storage capabilities, data input was often the limiting factor in mobile computing.
To facilitate data input, various methods have been developed. In one method, data are generated and manipulated on a desktop or laptop computer, and subsequently transferred to the PDA or other hand-held or pocketable device. While desktop or laptop based data generation, manipulation, and transfer are relatively convenient, manipulation and input of data into the PDA tends to be limited to points of use where a desktop or laptop computer are available. Moreover, additional equipment is required to enable a computer to transfer data to a PDA. For example, a cable, or an infrared transmitter may be used to facilitate transfer of data between a computer and a PDA.
In another method, a keyboard is attached to the PDA. Attachable keyboards are simple to use, however, many users experience difficulties operating the attachable keyboard due to its relatively small size (typically not larger than the PDA unit). To circumvent at least some of the problems associated with the small size of an attachable keyboard, foldable keyboards have been developed that increase the effective keyboard space two to three times when compared to non-foldable keyboards. Nevertheless, foldable and non-foldable keyboards must still be transported and attached to the PDA. Moreover, movable parts in a foldable keyboard typically increase the risk of mechanical or electrical failure.
In yet another method, the PDA includes a pressure or contact sensitive area that is employed to input and manipulate data in the PDA. While in some PDAs the sensitive area is a touch screen, other PDAs employ a touch pad-type input area. Regardless of the type of area, the input space is generally limited to a relatively small area. Moreover, and especially where large sets of data are modified in several subsequent operations, a relatively small screen is often not sufficient for proper and/or convenient data manipulation. A still further problem is that the input needs to be translated into text or other electronically processable format, which necessitates dedicated software to recognize manual data input. Another problem with a pressure or contact sensitive area, as with the other methods of input described above, is that at least some manual operation is required.
Thus, although various methods of data input to a PDA are known in the art, all of them suffer from one or more disadvantages. Therefore, there is still a need to provide improved methods and apparatus to facilitate data input into a PDA.